In low-bypass ratio turbofan engines, a fan is used to produce thrust in two manners. First, the fan pushes primary air into the core of the gas turbine engine for supplying air to a combustion process used to push gas through an exhaust nozzle. Second, the fan pushes bypass air past the core of the gas turbine engine to directly produce thrust. The fan is typically located at the inlet of the gas turbine engine within a fan case. The fan case is connected to an intermediate case that includes ducting for dividing the output of the fan into primary and bypass airstreams. The bypass air is routed around to the rear of the gas turbine engine, while the primary air is routed from the low pressure fan into the high pressure compressor (HPC) of the gas turbine core. The HPC comprises a series of rotating blades and stationary vanes for incrementally increasing the pressure of the primary air. These blades and vanes, starting with the first-stage blades, are sequentially housed within a high pressure compressor (HPC) case aft duct, which is connected to the immediate downstream face of the intermediate case. Thus, the first-stage blades receive air routed from the intermediate case. In order to optimize the incidence of the primary air onto the first-stage blades, a set of inlet guide vanes (IGVs) is provided between the intermediate case and the HPC case aft duct. The outer diameter ends of IGVs include trunnions that are inserted into bores in the HPC case aft duct. The inner diameter ends of the IGVs include trunnions that are inserted into an inner diameter shroud. In order to prevent the inner diameter of the IGVs from moving during operation of the gas turbine engine, especially during a surge event, the inner diameter shroud is pinned to the intermediate case with a surge retainer. In order to increase engine efficiency, it is desirable to seal the airflow path between the IGVs and the first-stage blades, while simultaneously minimizing the cavity space between the IGVs and the first-stage blades. Thus, there is a need for an IGV inner diameter retention and sealing mechanism that reduces the cavity between the IGVs and the first blade.